Collapsible swimming fins system for unidirectional thrust

Abstract

The system is configured as a modified swimming shoe with integrated support for collapsible fins positioned above the arch for short fins or above the arch and at the back of the swimming shoe to accommodate bigger fins. The system allows for maximum thrust during the power stroke while the resistance during the return stroke is no different from that of a barefoot swimmer due to the fins' passively switching to the collapsed position that closely mimics the dimensions of the foot. The resulting net efficiency of the propulsion thrust is much greater, and the complete movement (power stroke and return stroke) requires less energy and oxygen consumption. Collapsible fins offer greatly enhanced maneuverability by allowing abruptly changing direction and speed. The collapsible wrist fins further increase the efficiency of swimming while allowing the hand to remain free for other tasks.

1 . A swimming fin system, comprised of a swimming shoe, and a support frame for the attachment of an assembly of fins/stops above the arch of the foot. The system allows for a manner of swimming that is more suitable for human anatomy, and therefore more efficient. As opposed to movements imitating the undulating fish mode of swimming, collapsible fins also allow for direct backward thrust. 
     
     
         2 . The angle of attack, geometry, curvature, and size of the fins may vary depending on the degree of proficiency, comfort, and purpose. Larger fins can be accommodated by suitable modifications of the overall design including (but not limited to) thicker soles, higher positioning of the support frame, additional prongs in the support frame, and additional fin stops or hinges for limiting the range of fins' motion. 
     
     
         3 . The support frame can be either integrated with the swimming shoe or made attachable with straps as a separate unit. The design of the support frame may vary depending on aesthetic considerations. It may have, for example, 2, 3 or more prongs, or a solid/perforated surface design, and it can be manufactured from a range of suitable materials including (but not limited to) plastics, resins, or carbon fiber. 
     
     
         4 . The required range of motion of fins (from “open” to “closed” position) can be achieved using a variety of means including but not limited to external (in relation to fins) stops, 90O or 180O stop-hinges, and internal (in relation to fins) stops. The fins' moving parts, including hinges and armature, can also be integrated within the fin. The fins may also be equipped with straps that lock fins in the collapsed position to allow easy walking on the ground. 
     
     
         5 . In yet another embodiment, fins attached to the feet are complemented by similarly constructed wrist fins to further improve the efficiency of swimming, speed, and maneuverability.